1. Field of the Invention
This invention relates to dishwashing apparatus and, more particularly, to structure for supporting a plastic tub.
2. Background Art
It is known to construct tubs for dishwashing apparatus from plastic, thereby minimizing the cost of manufacture and overall weight of the apparatus. Various types of framework have been devised to support the tub, which is generally molded in a single piece. To best exploit the advantages of plastic, designers have striven to simplify the supporting framework for the tub. By minimizing the frame size, one contends with the problem of tub distortion, particularly about the opening at the front of the tub through which opening access is gained to a wash chamber defined by the tub.
One exemplary frame structure is shown in U.S. Pat. No. 3,826,553, to Cushing et al. Cushing et al disclose a raised platform for bearing against substantially the entire bottom wall of the tub and a wide collar that extends around the tub adjacent the front access opening.
The Cushing et al structure is quite complicated and has large supporting side plates which add considerably to the overall weight of the structure, thereby reducing the advantage of making the tub from lightweight plastic.
U.S. Pat. No. 4,295,692, to Jenkins, discloses a base upon which the tub can seat and a separate frame for surrounding and reinforcing the tub adjacent the front opening. Jenkins does not teach structure for positively joining the tub and base.
Another known prior art frame has front and rear, inverted, U-shaped collars which surround the upper portion of the tub. Frame members connect between the legs on each collar and separate frame members interconnect the collars with each other. This structure is also complicated and requires, during manufacture, performance of separate steps to connect the tub to the frame to prevent relative shifting therebetween.